The later API is nicer than the former, and is correct regarding wrap-around offsets (if anyone cares).
There are a few more places left with duplicated code, which I'll remove soon.
llvm-svn: 171259
such as by a compiler warning, a check in clang -fsanitizer=undefined, being
optimized to unreachable, or a combination of the above. PR14722.
llvm-svn: 171119
When the backend is used from clang, it should produce proper diagnostics
instead of just printing messages to errs(). Other clients may also want to
register their own error handlers with the LLVMContext, and the same handler
should work for warnings in the same way as the existing emitError methods.
llvm-svn: 171041
When the least bit of C is greater than V, (x&C) must be greater than V
if it is not zero, so the comparison can be simplified.
Although this was suggested in Target/X86/README.txt, it benefits any
architecture with a directly testable form of AND.
Patch by Kevin Schoedel
llvm-svn: 170576
This assumes (1 << n) is always not zero. Consider n is greater than word size.
Although I know it is undefined, this transforms undefined behavior hidden.
This led clang unexpected behavior with some failures. I will investigate to fix undefined shl in clang.
llvm-svn: 170128
In a previous thread it was pointed out that isPowerOfTwo is not a very precise
name since it can return false for powers of two if it is unable to show that
they are powers of two.
llvm-svn: 170093
Provides m_Argument that allows matching against a CallSite's specified argument. Provides m_Intrinsic pattern that can be templatized over the intrinsic id and bind/match arguments similarly to other pattern matchers. Implementations provided for 0 to 4 arguments, though it's very simple to extend for more. Also provides example template specialization for bswap (m_BSwap) and example of code cleanup for its use.
llvm-svn: 170091
been used in the first place. It simply was passed to the function and to the
recursive invocations. Simply drop the parameter and update the callers for the
new signature.
Patch by Saleem Abdulrasool!
llvm-svn: 169988
This change attempts to simplify (X^Y) -> X or Y in the user's context if we know that
only bits from X or Y are demanded.
A minimized case is provided bellow. This change will simplify "t>>16" into "var1 >>16".
=============================================================
unsigned foo (unsigned val1, unsigned val2) {
unsigned t = val1 ^ 1234;
return (t >> 16) | t; // NOTE: t is used more than once.
}
=============================================================
Note that if the "t" were used only once, the expression would be finally optimized as well.
However, with with this change, the optimization will take place earlier.
Reviewed by Nadav, Thanks a lot!
llvm-svn: 169317
missed in the first pass because the script didn't yet handle include
guards.
Note that the script is now able to handle all of these headers without
manual edits. =]
llvm-svn: 169224
This change tries to simmplify E1 = " X >> C1 << C2" into :
- E2 = "X << (C2 - C1)" if C2 > C1, or
- E2 = "X >> (C1 - C2)" if C1 > C2, or
- E2 = X if C1 == C2.
Reviewed by Nadav. Thanks!
llvm-svn: 169182
Sooooo many of these had incorrect or strange main module includes.
I have manually inspected all of these, and fixed the main module
include to be the nearest plausible thing I could find. If you own or
care about any of these source files, I encourage you to take some time
and check that these edits were sensible. I can't have broken anything
(I strictly added headers, and reordered them, never removed), but they
may not be the headers you'd really like to identify as containing the
API being implemented.
Many forward declarations and missing includes were added to a header
files to allow them to parse cleanly when included first. The main
module rule does in fact have its merits. =]
llvm-svn: 169131
The simplify-libcalls pass maintained a statistic to count the number
of library calls that have been simplified. Now that library call
simplification is being carried out in instcombine the statistic should
be moved to there.
llvm-svn: 168975
depends on the IR infrastructure, there is no sense in it being off in
Support land.
This is in preparation to start working to expand InstVisitor into more
special-purpose visitors that are still generic and can be re-used
across different passes. The expansion will go into the Analylis tree
though as nothing in VMCore needs it.
llvm-svn: 168972
My commit to migrate the printf simplifiers from the simplify-libcalls
in r168604 introduced a regression reported by Duncan [1]. The problem
is that in some cases the library call simplifier can return a new value
that has no uses and the new value's type is different than the old value's
type (which is fine because there are no uses). The specific case that
triggered the bug looked something like:
declare void @printf(i8*, ...)
...
call void (i8*, ...)* @printf(i8* %fmt)
Which we want to optimized into:
call i32 @putchar(i32 104)
However, the code was attempting to replace all uses of the printf with
the putchar and the types differ, hence a crash. This is fixed by *just*
deleting the original instruction when there are no uses. The old
simplify-libcalls pass is already doing something similar.
[1] http://lists.cs.uiuc.edu/pipermail/llvmdev/2012-November/056338.html
llvm-svn: 168716
InstCombineLoadStoreAlloca.cpp, which had many issues.
(At least two bugs were noted on llvm-commits, and it was overly conservative.)
Instead, use getOrEnforceKnownAlignment.
llvm-svn: 168629
Enhancement to InstCombine. Try to catch this opportunity:
---------------------------------------------------------------
((X^C1) >> C2) ^ C3 => (X>>C2) ^ ((C1>>C2)^C3)
where the subexpression "X ^ C1" has more than one uses, and
"(X^C1) >> C2" has single use.
----------------------------------------------------------------
Reviewed by Nadav (with minor change per his request).
llvm-svn: 168615
When code deletes the context, the AttributeImpls that the AttrListPtr points to
are now invalid. Therefore, instead of keeping a separate managed static for the
AttrListPtrs that's reference counted, move it into the LLVMContext and delete
it when deleting the AttributeImpls.
llvm-svn: 168354
replaced by this patch is equivalent to the new logic, but you'd be wrong, and
that's exactly where the bug was. There's a similar bug in instsimplify which
manifests itself as instsimplify failing to simplify this, rather than doing it
wrong, see next commit.
llvm-svn: 168181
This patch migrates the math library call simplifications from the
simplify-libcalls pass into the instcombine library call simplifier.
I have typically migrated just one simplifier at a time, but the math
simplifiers are interdependent because:
1. CosOpt, PowOpt, and Exp2Opt all depend on UnaryDoubleFPOpt.
2. CosOpt, PowOpt, Exp2Opt, and UnaryDoubleFPOpt all depend on
the option -enable-double-float-shrink.
These two factors made migrating each of these simplifiers individually
more of a pain than it would be worth. So, I migrated them all together.
llvm-svn: 167815
In some cases the library call simplifier may need to replace instructions
other than the library call being simplified. In those cases it may be
necessary for clients of the simplifier to override how the replacements
are actually done. As such, a new overrideable method for replacing
instructions was added to LibCallSimplifier.
A new subclass of LibCallSimplifier is also defined which overrides
the instruction replacement method. This is because the instruction
combiner defines its own replacement method which updates the worklist
when instructions are replaced.
llvm-svn: 167681